2006 Suburban front Air conditioning issue

[fgross2006]

Hopefully this is an acceptable post in the non FEP forum.

My 200 Suburban has has issues with the front AC system randomly blowing warm/hot air for 2 summers. This has been an ongoing issue I've been chasing and its getting frustrating.

My mechanic suggested the compressor was tired so I just wasted $ on parts and labor for a brand new AC compressor that did not solve the problem. The rear AC system blows ice cold. Just not the front.

I replaced the orifice tube for the second time, blend door actuator, the blower motor resistor and the AC pressure switch that mounts on the accumulator cannister, both genuine AC Delco parts. I replaced the HVAC Control panel with a brand new Dorman 599-211.

The Dorman reprogrammed itself as soon as it powered up. I tried reprograming the blend door by pulling the fuse and letting it relearn. When I do that the issue gets worse and blows hot air for awhile after going through the re program routine.

My mechanic wants me to replace the orifice tube and blend door with genuine AC Delco, which I have ordered for tomorrow. But I am skeptical on this.

All my Googling and youtubing have brought me to vids that say its the blend door and my 2006 suburban only has one. Something else electronic is causing a random hot to cold issue in the front system only. I've dumped so much money is parts and labor chasing this issue. I hate to go to the dealer but I'm out of idea.

[qikgts]

Did you get anywhere with this?

Cabin air temp sensor may be the issue. I believe this one goes in the front headliner and if the issue is just happening in the front, it may be worth the few bucks considering what an hour of diag at the dealer is gonna cost.

https://www.rockauto.com/en/moreinfo...=14376&jsn=942

This next one, I think installs in the ducts to allow the system to sense temp in each duct for multi zone temp controls. I doubt the whole front would be having an issue if one of these went bad. Also pretty sure you would also need to have independent temp control for driver and passenger to need them anyway.

https://www.rockauto.com/en/moreinfo...=14376&jsn=940

[fgross2006]

Did you get anywhere with this?

Cabin air temp sensor may be the issue. I believe this one goes in the front headliner and if the issue is just happening in the front, it may be worth the few bucks considering what an hour of diag at the dealer is gonna cost.

https://www.rockauto.com/en/moreinfo...=14376&jsn=942

This next one, I think installs in the ducts to allow the system to sense temp in each duct for multi zone temp controls. I doubt the whole front would be having an issue if one of these went bad. Also pretty sure you would also need to have independent temp control for driver and passenger to need them anyway.

https://www.rockauto.com/en/moreinfo...=14376&jsn=940

I did finally solve this. I replaced the cabin air sensor 2 years back when I got the SUV because of heat problems. Those sensors will cause you get cold air unless your set at 90 degrees. And you'll bake.

But the AC was a frustrating journey. I swapped the HVAC panel 3 times. No change. I changed a sensor thats behind the grill, no change, put in a new compressor, new blend door actuator, no change. Constantly getting cold/warm and it got worse till it was warm 90% of the time, then suddenly ice cold for 30 seconds. I was about to replace the duct sensors next, requiring a partial dash pull. Then my mechanic suddenly thought of the accumulator. Honestly, its considered good practice to change the accumulator together with a new compressor and neither of us thought the accumulator looked old or bad.

A light bulb in his head went off while we were standing by the car idling and the compressor kicked on, he started feeling hoses and said the accumulator is supposed to be ice cold when the AC compressor is engaged. It wasn't.

For $22 in parts and $100 in labor that was what corrected it. The only bad thing is when he purged the system he said it was low on refrigerant. Since we had replaced the compressor barely a month prior and the system was charged with a fill of freon. That means I have a slow leak somewhere which Ill have to wait till next spring to locate. For now, I still get cold AC

And it wasn't low freon that caused the warm air because the day we installed the compressor and charged it and still got warm air.

Never hesitate to change the accumulator.

[fgross2006]

I did finally solve this. I replaced the cabin air sensor 2 years back when I got the SUV because of heat problems. Those sensors will cause you get cold air unless your set at 90 degrees. And you'll bake.

But the AC was a frustrating journey. I swapped the HVAC panel 3 times. No change. I changed a sensor thats behind the grill, no change, put in a new compressor, new blend door actuator, no change. Constantly getting cold/warm and it got worse till it was warm 90% of the time, then suddenly ice cold for 30 seconds. I was about to replace the duct sensors next, requiring a partial dash pull. Then my mechanic suddenly thought of the accumulator. Honestly, its considered good practice to change the accumulator together with a new compressor and neither of us thought the accumulator looked old or bad.

A light bulb in his head went off while we were standing by the car idling and the compressor kicked on, he started feeling hoses and said the accumulator is supposed to be ice cold when the AC compressor is engaged. It wasn't.

For $22 in parts and $100 in labor that was what corrected it. The only bad thing is when he purged the system he said it was low on refrigerant. Since we had replaced the compressor barely a month prior and the system was charged with a fill of freon. That means I have a slow leak somewhere which Ill have to wait till next spring to locate. For now, I still get cold AC

And it wasn't low freon that caused the warm air because the day we installed the compressor and charged it and still got warm air.

Never hesitate to change the accumulator.

So this headache has returned. Last year after replacing the accumulator I had ice cold AC the duration of the summer. I just started putting the AC on and once again I get ice cold from rear and passenger vents but 90 degrees from driver side vents.

[scenarioL113]

Do you think possibly the "blend door" is not closing or opening?

If you compressor is working then I do not think you are low on freon.